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1.
Front Cell Infect Microbiol ; 13: 1196084, 2023.
Article in English | MEDLINE | ID: mdl-37621875

ABSTRACT

Purpose: To determine the role of Lactobacillus strains and their combinations in inhibiting the colonization of H. pylori and gastric mucosa inflammation. Methods: Human gastric adenocarcinoma AGS cells were incubated with H. pylori and six probiotic strains (Lactobacillus acidophilus NCFM, L. acidophilus La-14, Lactiplantibacillus plantarum Lp-115, Lacticaseibacillus paracasei Lpc-37, Lacticaseibacillus rhamnosus Lr-32, and L. rhamnosus GG) and the adhesion ability of H. pylori in different combinations was evaluated by fluorescence microscopy and urease activity assay. Male C57BL/6 mice were randomly divided into five groups (uninfected, H. pylori, H. pylori+NCFM, H. pylori+Lp-115, and H. pylori+NCFM+Lp-115) and treated with two lactobacilli strains (NCFM and Lp-115) for six weeks. H. pylori colonization and tissue inflammation statuses were determined by rapid urease test, Hematoxylin-Eosin (HE) staining, immunohistochemistry, and qRT-PCR and ELISA. Results: L. acidophilus NCFM, L. acidophilus La-14, L. plantarum Lp-115, L. paracasei Lpc-37, L. rhamnosus Lr-32, and L. rhamnosus GG reduced H. pylori adhesion and inflammation caused by H. pylori infection in AGS cells and mice. Among all probiotics L. acidophilus NCFM and L. plantarum, Lp-115 showed significant effects on the H. pylori eradication and reduction of inflammation in-vitro and in-vivo. Compared with the H. pylori infection group, the mRNA and protein expression levels of IL-8 and TNF-α in the six Lactobacillus intervention groups were significantly reduced. The changes in the urease activity (ureA and ureB) for 1-7h in each group showed that L. acidophilus NCFM, L. acidophilus La-14, L. plantarum Lp-115, and L. rhamnosus GG effectively reduced the colonization of H. pylori. We observed a higher ratio of lymphocyte and plasma cell infiltration into the lamina propria of the gastric mucosa and neutrophil infiltration in H. pylori+NCFM+Lp-115 mice. The infiltration of inflammatory cells in lamina propria of the gastric mucosa was reduced in the H. pylori+NCFM+Lp-115 group. Additionally, the expression of IFN-γ was decreased significantly in the NCFM and Lp-115 treated C57BL/6 mice. Conclusions: L. acidophilus NCFM and L. plantarum Lp-115 can reduce the adhesion of H. pylori and inhibit the gastric inflammatory response caused by H. pylori infection.


Subject(s)
Gastritis , Helicobacter pylori , Humans , Male , Animals , Mice , Mice, Inbred C57BL , Lactobacillus acidophilus , Urease , Disease Models, Animal , Gastritis/prevention & control , Inflammation , Lactobacillus
2.
iScience ; 23(6): 101168, 2020 Jun 26.
Article in English | MEDLINE | ID: mdl-32480129

ABSTRACT

An unprecedented desaturation method via redox-neutral hydrogen transfer process has been disclosed under mild conditions for the selective formation of terminal alkene with alkyl diazo compounds and aza-o-QMs. The control experiments and DFT calculations suggest that the visible light was introduced as a key parameter to enhance the reactivity via a radical process in the formation of closed-shell cyclopropane intermediate, followed by a ring opening and redox-neutral hydrogen transfer process to give the desaturated product. The high regioselectivity in this transformation is enabled by the internal amino species as an ancillary group (AG) in the final olefin formation step. This method provides a missing link in the expeditious preparation of synthetically useful 2-allyl anilines with broad substrate generality. Further applications of these generated products in N-heterocycle construction, including 5- and 6-membered rings with structural diversity, have been tactfully explored, which highlight the potential in methodology development and drug discovery.

3.
Nat Prod Res ; 34(10): 1373-1379, 2020 May.
Article in English | MEDLINE | ID: mdl-30445878

ABSTRACT

The fresh leaves of Metapanax delavayi (Araliaceae) have been used as a common wild vegetable for salad and soup, and also herbal tea by the local people living in its growing areas of Yunnan province, China. Detailed chemical investigation led to the identification of a new triterpenoid saponin, 3-O-α-L-arabinopyranosyl-28-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranosyl-3ß-hydroxyolean-12-ene-28,29-dioic acid (1) from the fresh leaves, together with 11 known compounds, including six triterpenoid saponins (2-7), two caffeoylquinic acid derivatives (8-9), and three flavonoid glycosides (10-12). Their structures were determined on the basis of spectroscopic analysis and acidic hydrolysis. Compounds 3-5 and 8-12 were isolated from M. delavayi for the first time. Moreover, the known saponins 3-O-ß-D-xylopyranosyl-3ß-hydroxyolean-12-ene-28,29-dioic acid (3) and yiyeliangwanoside IV (5) exhibited protective effects on HepG2 cells damaged by the alcohol intakes, at a concentration of 1.0 µg/mL. The results indicated M. delavayi is an ideal dietary vegetable and herbal tea with potential hepatoprotective activity.[Formula: see text].


Subject(s)
Araliaceae/chemistry , Plant Leaves/chemistry , Protective Agents/isolation & purification , Saponins/isolation & purification , Triterpenes/isolation & purification , China , Glycosides/analysis , Hep G2 Cells/drug effects , Humans , Molecular Structure , Plant Extracts/chemistry , Protective Agents/chemistry , Protective Agents/pharmacology , Saponins/chemistry , Saponins/pharmacology , Triterpenes/analysis , Triterpenes/chemistry , Triterpenes/pharmacology
4.
Chem Commun (Camb) ; 54(64): 8889-8892, 2018 Aug 07.
Article in English | MEDLINE | ID: mdl-30043020

ABSTRACT

An efficient and convenient ligand-free, rhodium-catalyzed ortho-C(sp2)-H amidation of benzaldehydes with dioxazolones using H2O as the key promoter is described. Using this protocol, a wide range of benzaldehyde substrates were selectively amidated in good to excellent yields with broad functional group compatibility. KIE experiments revealed that the C-H bond activation was likely the rate-limiting step. In addition, computational studies indicated that the catalyst precursor interacted with water and dioxazolones to generate the active catalytic species. Notably, the practicality and efficacy of this method were illustrated by a late-stage amidation of an estrone-derived molecule and further transformations of the amidated product.

6.
J Agric Food Chem ; 58(15): 8820-4, 2010 Aug 11.
Article in English | MEDLINE | ID: mdl-20681670

ABSTRACT

Camellia pachyandra Hu. is a species in Camellia sect. Heterogenea (Theaceae), whose leaves have been used for making tea and consumed by the local people living in Yunnan province, China. This is the first investigation of the chemical constituents in the leaves of C. pachyandra, from which 22 phenolic compounds including nine hydrolyzable tannins (1-9), 11 flavonol glycosides (10-20), and two simple phenolics (21, 22) were isolated. It was noted that the leaves of the title plant contained no caffeine and no catechin, whereas hydrolyzable tannins were found to be the major constituents, of which the content of ellagitannin 5 reached to 3.7%. All the isolates were evaluated for their antioxidant activities by DPPH radical scavenging and tyrosinase inhibitory assays. Though the secondary metabolites without caffeine and catechins are different from the commonly consumed tea plants, the results suggested that the leaves of C. pachyandra, rich in hydrolyzable tannins as potent antioxidants, could be developed as an ideal resource for a natural beverage without caffeine.


Subject(s)
Antioxidants/analysis , Camellia/chemistry , Phenols/analysis , Plant Extracts/analysis , Antioxidants/isolation & purification , China , Phenols/isolation & purification , Plant Extracts/isolation & purification , Plant Leaves/chemistry
7.
J Agric Food Chem ; 56(16): 7517-21, 2008 Aug 27.
Article in English | MEDLINE | ID: mdl-18636681

ABSTRACT

The chemical constituents of green tea prepared from the leaves of Camellia taliensis (W. W. Smith) Melchior (Theaceae) were investigated for the first time. Of these, 19 phenolic compounds including 8 hydrolyzable tannins (1-8), 6 catechin derivatives (9-14), 3 quinic acid aromatic esters (15-17), and 2 simple phenolics (18, 19) were identified, along with caffeine (20). Their antioxidant activities were evaluated by DPPH radical scavenging and tyrosinase inhibitory assays. Moreover, the chemical composition was compared with that in the cultivated tea plant, C. sinensis var. assamica, by HPLC analysis. It was noted that C. taliensis has similar chemical features with the cultivated tea plant; that is, both of them contain rich flavan-3-ols and caffeine. In addition, there are abundant hydrolyzable tannins as specific characteristic constituents contained in the leaves of C. taliensis. Therein, 1,2-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-beta-D-glucopyranose (8), as a major compound in C. taliensis, showed remarkable antioxidant activity. The results suggested that C. taliensis could be a valuable plant resource for the production of tea.


Subject(s)
Antioxidants/analysis , Beverages/analysis , Camellia/chemistry , Phenols/analysis , Plant Leaves/chemistry , Catechin/analogs & derivatives , Catechin/analysis , Quinic Acid/analogs & derivatives , Quinic Acid/analysis , Tannins/analysis
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